Catheters have long been used for injecting fluids into the central venous circulation. Needles and relatively short peripherally inserted venous catheters (PIVC) are used for routine blood draws and fluid administrations. Central catheters discharge fluids centrally in the venous vasculature, and are commonly used for administering drugs that are too damaging to the veins to administer peripherally, for example, some chemotherapy, antibiotics, and parenteral nutrition. If the catheter and/or the veins are large enough and strong enough, they can be used for the rapid injection of contrast agents for imaging procedures such as, for example, CT, MR, ultrasound, and molecular imaging studies. PIVC lines are generally inexpensive and can be placed or installed by normal nurses or in some cases by specially trained phlebotomists.
Longer central catheters and infusion ports are, generally, placed into veins in the chest or neck and usually require surgery to be inserted into the vein. More recently, long flexible catheters generally referred to as peripherally inserted central catheter (PICC) have replaced infusion ports that are surgically implanted. These PICC lines can be inserted through a vein in the arm into the central venous circulation near the heart by trained nurses providing a more economic and patient friendly means for inserting a central catheter or infusion port. Generally, a guide wire is provided in the lumen of the flexible catheter to provide rigidity during the insertion procedure and a stiff needle, optionally with a dilator, is used to gain access to the vessel. The insertion procedure is carried out using a fluoroscope (or an ultrasonic imaging device) to help the user guide the catheter through the vessel into the central vena cava and to confirm proper placement of the catheter tip. Once in place, the needle or guide wire is removed, leaving the flexible catheter with the distal tip properly positioned for injection of fluid. These catheters can be left in place for days to months for the low flow-rate infusion of medication into the patient, and/or for sampling blood in patients with veins that have been compromised by disease or by the corrosive effects of chemotherapeutic drugs. The issues with PICC placement, phlebitis, and irritation or damage to the vessels and/or the heart have been made worse to some extent by the increased use of Power PICCs which can accommodate the pressures generated during the injection of CT contrast. This is because they often are made of a stiffer, stronger plastic and similarly may be larger in size to provide sufficient flow rates for the use in imaging procedures.
However, insertion of a PICC line has several challenges and drawbacks. The long, relatively stiff catheter and/or guide wire requires the creation and maintenance of a large sterile field around the insertion point so as to not contaminate the catheter or guidewire before insertion into the body. During insertion, the PICC line can catch on valves and tight bends in blood vessels, potentially causing trauma to blood vessels. In addition, because of the sometimes tortuous path of the veins, it can be difficult to move or remove the guidewire relative to the catheter during installation or when installation is complete. Similarly, a stiff tip on the PICC line can irritate a patient's heart if the PICC line is inserted too far or damage the superior vena cava if not inserted far enough. If the catheter is too large or stiff, it can damage the peripheral vein through which passes. This can lead to complications such as thrombosis, pain, and infection. Because of the importance of the correct placement of the catheter tip, the procedure was historically done under fluoroscopy in an interventional suite. At the location where the catheter exits the patient's skin, the stiffness of the catheter also increases the likelihood of motion and disruption of the seal between the catheter and the skin which can increase the possibility of infection.